Fiber optic module and sytem including rear connectors

ABSTRACT

A telecommunications assembly including a housing and a plurality of modules mounted within the housing. The modules includes a rear face in which is mounted at least one fiber optic connector. Within an interior of the housing are positioned at least one fiber optic adapters. Inserting the module through a front opening of the housing at a mounting location positions the connector of the module for insertion into and mating with the adapter of the housing. The adapters within the interior of the housing are mounted to a removable holder. A method of mounting a telecommunications module within a chassis.

FIELD

The present invention generally relates to fiber optictelecommunications equipment. More specifically, the present inventionrelates to fiber optic modules and chassis for holding fiber opticmodules.

BACKGROUND

In fiber optic telecommunications systems, it is common for opticalfibers of transmission cables to be split into multiple strands, eitherby optical splitting of a signal carried by a single stranded cable orby fanning out the individual fibers of a multi-strand cable. Further,when such systems are installed, it is known to provide excess capacityin the installations to support future growth and utilization of thefibers. Often in these installations, modules including splitters orfanouts are used to provide the connection between transmission fibersand customer fibers. To reduce the cost and complexity of the initialinstallation and still provide options for future expansion, a modulemounting chassis capable of mounting multiple modules may be used insuch an installation.

While the chassis may accept several modules, the initial installationmay only include fewer modules mounted in the chassis, or enough toserve current needs. These chassis may be configured with limited accessto one or more sides, or may be mounted in cramped locations. Inaddition, some of these chassis may be pre-configured with the maximumcapacity of transmission cables to accommodate and link to modules whichmay be installed in the future. Since it is desirable to have access tocomponents within the chassis for cleaning during the installation of anew module, some provision or feature of the chassis will desirablypermit a user to access and clean the connectors of thesepre-connectorized and pre-installed transmission cables.

It is also desirable for the chassis to be configured to ensure thatmodules are installed correctly and aligned with other components withinthe chassis to mate with the pre-connectorized and pre-installedtransmission cables.

SUMMARY

The present invention relates to a telecommunications assembly includinga housing and a plurality of modules mounted within the housing. Themodules includes a rear face in which is mounted at least one fiberoptic connector. Within an interior of the housing are positioned atleast one fiber optic adapters. Inserting the module through a frontopening of the housing at a mounting location positions the connector ofthe module for insertion into and mating with the adapter of thehousing. The adapters within the interior of the housing are mounted toa removable adapter holder. The present invention further relates to amethod of mounting a telecommunications module within a chassis.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the description, illustrate several aspects of the invention andtogether with the detailed description, serve to explain the principlesof the invention. A brief description of the drawings is as follows:

FIG. 1 is a front perspective view of a telecommunications assembly witha plurality of fiber optic modules installed through a front opening.

FIG. 2 is a front perspective of the telecommunications assembly of FIG.1, taken from an opposite side.

FIG. 3 is a front view of the telecommunications assembly of FIG. 1.

FIG. 4 is a top view of the telecommunications assembly of FIG. 1.

FIG. 5 is a rear view of the telecommunications assembly of FIG. 1.

FIG. 6 is a side view of the telecommunications assembly of FIG. 1.

FIG. 7 is a front perspective view of the telecommunications assembly ofFIG. 1, with one of the modules exploded out of the assembly andmounting flanges removed from the upper and lower surfaces of thechassis.

FIG. 8 is a rear perspective view of the telecommunications assembly ofFIG. 7.

FIG. 9 is a side view of the telecommunications assembly of FIG. 7, witha fiber optic adapter holder exploded out of the assembly.

FIG. 10 is a side cross-sectional view of the telecommunicationsassembly of FIG. 1, taken through the center of one of the modulesmounted within the assembly.

FIG. 11 is a front view of the telecommunications assembly of FIG. 1,with one of the modules removed to show the adapter holder mountedwithin the interior of the assembly.

FIG. 12 is a front perspective view of the adapter holder of FIG. 11,removed from the assembly.

FIG. 13 is a front view of the adapter holder of FIG. 12.

FIG. 14 is a rear view of the adapter holder of FIG. 12.

FIG. 15 is a side view of the adapter holder of FIG. 12.

FIG. 16 is a top view of the adapter holder of FIG. 12.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentinvention which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or similar parts.

FIG. 1 illustrates a telecommunications assembly 10 with mountinglocations 12 for mounting a plurality of modules 14. Assembly 10includes a chassis or housing 16 with a first major side 18, a secondmajor side 20 and a pair of opposing transverse sides 22 extendingbetween the first and second major sides. A mounting flange 24 may bemounted to each of the major sides extending generally oppositely ofeach other. A secondary or alternative mounting flange 26 may also bemounted to one of the major sides to provide options for mountinghousing 16 to a particular size or shape of equipment rack, cabinet orother type of installation.

Housing 16 defines a front opening 28 through which modules 14 areinserted within an interior 30 (shown below in FIG. 7) of housing 16.Openings 32 may be defined in the transverse sides 22 to permit accessby a person into interior 30. Openings 32 may include a protective pad34 about a perimeter to provide chafe and other injury to any handswhich may pass into or out of interior 30 through one of the openings32. Visible through opening 32 in FIG. 1 is a housing 40 of one of themodules 14 mounted within front opening 28. Flanges 24 and 26 mayinclude a plurality of fastener openings 36 for mounting housing 16where needed in a telecommunications installation.

Referring now to FIG. 2, each module 14 includes a releasably catch 42adjacent second major side 20. As can be seen below in and describedwith to FIG. 10, catch 42 engages a portion of housing 16 to hold module14 within front opening 28 and can also be deflected to permitwithdrawal of module 14 from housing 16. Each module 14 also may includeone or more cable exits 44 extending from a front face 46. Cable exits44 permit telecommunications cables within module 14 to be directedoutside of module 14, as will be described below with regard to FIG. 10.As shown in FIG. 2, front faces 46 of modules 14 are angled with regardto front opening 28, which may aid in the direction of cables exitingmodule 14 toward a desired location in the telecommunicationsinstallation. It is anticipated that front faces 46 could be madegenerally parallel to front edges 38 of transverse sides 22 at frontopening 28 within the scope of the present disclosure.

Referring now to FIG. 3, modules 14 includes unequal length flanges 48and 50 which are received within correspondingly sized slots 52 and 54,respectively. Flange 48 and slot 52 are smaller in size than flange 50and slot 54. Slot 52 is sized so that, while flange 48 may be receivedwithin slot 52, larger flange 50 will not fit. This ensures that modules14 are positioned within front opening 28 in a particular desiredorientation. Similar flanges are described in commonly-owned U.S. Pat.No. 5,363,465, the disclosure of which is incorporated herein byreference. Opposite latch 42 and mounted to housing 16 at each mountinglocation 12 are an adapter holder 56 releasably held within frontopening 28 by a thumbscrew 58. Adapter holder 56 is described in furtherdetail below with regard to FIGS. 9 to 16.

Referring now to FIGS. 4 and 5, housing 16 further includes a back 60opposite front opening 28, substantially closing off the rear of housing16. Openings may be provided through back 60 to allow cables or air topass, but it is anticipated that user access into interior 30 of housing16 will be made through front opening 28. As shown in FIG. 6, on one endof modules 14, a lip or finger grip 62 may be included to aid removal ofmodule 14 from housing 16. Finger grip 62 is preferably positioned onmodule 14 opposite latch 42 so that a user may apply opposing force withfingers or hands to securely grasp the module and remove it from housing16.

Referring now to FIG. 7, latch 42 of module 14 includes a recessed area66 which engages an edge 64 of mounting location 12 to hold module 14 inplace within front opening 28. Recessed area 66 is formed near a distalend of latch 42 and a flexible portion 68 extends from recessed area 66to a point of connection to a first side 70 of module 14. Flexibleportion 68 is resiliently deformable and allows a user to deflect latch42 to disengage recessed area 66 from edge 64 and remove module 14 fromhousing 16 or for latch 42 to deflect as module 14 is inserted intofront opening 28 and engage edge 64. Module 14 includes a secondopposing side 72 and a back 78. An intermediate rear face 76 is formedin second side 72 by an inset side portion 74. A pair of fiber opticconnectors 80 is positioned in rear face 76 to mate with fiber opticadapters mounted to adapter holder 56 within interior 30 of housing 16.

Module housing 40 also includes a first transverse face 82 extendingbetween first side 70, second side 72, back 78 and front face 46. Asecond transverse face 84 closes off the opposite side of module housing40 between front face 46 and back 78 but extends beyond sides 70 and 72to form flanges 48 and 50 (flange 50 is not visible in FIG. 7). In FIG.8, flange 50 is visible as an extension of second transverse face 84beyond side 70 of module 14. Module housing 40 may include curvedtransitions 86 between sides 70 and 72 and back 78. Transitions 86 maybe shaped to provide bend radius protection to cables within interior 30as the cables extend to adapters 88. Alternatively, sides 70 and 72 mayterminate directly at back 78, depending on the needs for placingcomponents within module housing 40 and efficiencies in manufacturing ofmodule housing 40.

FIG. 9 shows assembly 10 with adapter holder 54 exploded out frominterior 30. Holder 54 includes an extension 86 to hold and position apair of adapters 88 to engage connectors 80 of module 14. Each adapter88 includes a first or rear end 90 and a second or front end 92, andeach of the first and second ends are adapted to receive a fiber opticconnector which may terminate a fiber optic cable.

FIG. 10 shows a cross-section of assembly 10 with a first cable 94extending from connector 80 to an optical component 98, mounted withinan interior 96 of module housing 40. Optical component 98 may be asplitter or a fan-out or another type of optically significant element.First cable 94 may be a multi-strand fiber cable with a plurality ofstrands of optical fiber and optical component 98 may be a fanout toseparate the individual strands into each of a plurality of secondcables 100. Second cables 100 extend from optical component 98 to cableexit 44. Alternatively, first cable 94 may be a single fiber whosesignal is separated by optical component 98 which is a splitter and aplurality of second cables 100 carrying portions of the signal fromfirst cable 94 may extend to cable exit 44. The arrangement of opticalfiber and sheathing at cable exit 44 may be as disclosed incommonly-owned U.S. patent application Ser. No. 10/658,802, thedisclosure of which is incorporated herein by reference.

An outside cable 102 may extend to rear end 90 of adapter 88 and beterminated by a connector 104. Connector 104 may be received in rear end90 to be optically connected to connector 80 of module 14. Cable 102 mayextend from interior 30 of housing 16 through an opening in one of sides18, 20, or 22 in housing 16.

Referring now to FIG. 11, assembly 10 has a module removed from one ofthe mounting locations 12 and includes an alternative adapter holder 154in that mounting location 12. Holder 154 includes a shield 108 in frontof second ends 92 of adapters 88. In some installations, a housing 16may be installed and a cable 102 led to and connected to first ends 90of adapters 88, before a module 14 is placed in the associated mountinglocation 12. If cable 102 is illuminated and transmitting light signals,shield 108 will prevent accidental exposure to these signals which mightdamage eyes or other sensitive organs, or nearby communicationsequipment.

In FIG. 12, holder 154 includes an opening 124 through extension 86through which adapters 88 are mounted. Thumbscrew 56 extends through afront flange 114 and pair of wall engaging flanges 116 extend backwardfrom adjacent front flange 114. Alternatively, other releasablefeatures, such as snap fit devices, quarter turn fasteners, swelllatches or similar features may be used in place of thumbscrew 56 onholder 54 or 154. Positioned between a forward end of each flange 116and front flange 114 is a slot 118. Toward a rear end of flanges 116 area pair of wall slots 120. As shown in FIG. 10, an inner wall 110 ispositioned within interior 30 offset inwardly from first major surface18. Wall slots 120 extend along both sides of inner wall 110. Aturned-in forward edge 112 of first major surface 18 engages slot 118.These engagements between housing 16 and holder 154 correctly positionadapters offset from inner wall 110 within interior 30 to engageconnector 80 on rear face 76 of module 14. A central member 122 extendsfrom front flange 114 between wall flanges 116 to extension 86 tocorrectly position adapters 88 within interior 30 between front opening28 and rear 60.

Referring now to FIGS. 13 to 16, extension 86 of holder 154 includes aplurality of fastener openings 124 for mounting adapters 88 to extension86. Fasteners 126 may be extended through side flanges 128 of adapter 88to permit secure mounting of adapters 88. Adapters 88 are shown as SCstyle connectors, although other types, styles and formats of adaptersmay be used within the scope of the present disclosure and connectors 80and 104 changed to mate with these alternative adapters. Within each ofthe adapters 88 shown may be an alignment device, such as a split sleeve130 to correctly position optical fiber terminated in a ferrule and heldby connectors 80 and 104. Such alignment devices and terminationferrules are well known in the art.

Shield 108 is curved when viewed from the side, as in FIG. 15, so thatshield 108 will be deflected by module 14 as module 14 is inserted intointerior 30 through front opening 28 so that connectors 80 can mate withadapters 88. Shield 108 is preferably made of a resilient deformablematerial that will return to the position shown in FIG. 154 when themodule 14 is withdrawn from mounting location 12. Shield 108 may beconnected to central member 122 by a pair of fasteners such as screws132. Alternatively, shield 108 could be connected to holder 154 by beingformed integrally with holder 154 or by spot-welding or other fasteningtechniques. As rear 60 closes off the rear of housing 16 so that is noaccess to the rear any modules 14 mounted at a mounting location 12,providing a second shield 108 to block light from first end 90 of eachadapter 88 is not needed as shown. However, if any sensitive equipmentis mounted within module 14 or housing 16, it may be desirable to have asecond shield 108 blocking first side 90 of adapters 88.

Insertion of module 14 into housing 16 at one of the mounting locations12 may include first unfastening thumbscrew 56 and removing holder 54 or154 from interior 30 through front opening 28. Cable 102 preferablyincludes enough excess length or slack within interior 30 to permitadapters 88 to be pulled through opening 28. Once positioned outside ofinterior 30, connector 104 of cable 102 can be removed from first end 90of adapter 88 to permit a polished endface of an optical fiber withincable 102 to be cleaned. Connector 104 can then be reinserted withinfirst end 90. Holder 54 or 154 can be reinserted within interior 30 sothat the holder engages inner wall 110 and inward turned extension 112and thumbscrew 56 resecured. Insertion of module 14 into front opening28 begins the mating of module 14 to housing 16 and adapters 88. Flanges48 and 50 engage slots 52 and 54, respectively, as module 14 isinserted. Connectors 80 and portions of second side 72 engage anddeflect shield 108 (if present) as connectors 80 approach second ends 92of adapters 88. Further insertion of module 14 brings connectors 80 intoand contact with adapters 88 and the connectors are received withinsecond ends 92. Latch 42 is deflected inward as module 14 is insertedand then springs back so that recessed area 66 engages edge 64. Module14 is now mounted within front opening 28 and interior 30 at mountinglocation 12 and in position to process and transmit signals from cable102 through first cable 94, optical component 98 and second cable 100within module interior 96.

The above specification, examples and data provide a completedescription of the manufacture and use of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention resides in the claimshereinafter appended.

1. A telecommunications assembly comprising: a chassis and a modulemounted within the chassis; the chassis including: a housing with a top,a bottom, and opposing sides, defining an interior space accessiblethrough an open front, the interior space substantially closed off by aback opposite the open front; at least one mounting location within theinterior space; at least one fiber optic adapter corresponding to eachof the mounting locations mounted within the interior space, the fiberoptic adapters each including a front end directed toward the open frontand a back end directed toward the back, each end configured to receivea fiber optic connector; and, the fiber optic adapters mounted to aholder adjacent one of the sides of the chassis, the holder removablefrom the interior through the open front of the chassis to permit accessto the back end of the adapters mounted to the holder, the holderpositioning the adapters within the interior behind the open front; and,the module mounted at one of the mounting locations and including ahousing with a rear face to which is mounted at least one fiber opticconnector engaging the at least one fiber optic adapter of the chassis.2. The telecommunications assembly of claim 1, the module furthercomprising: a housing enclosing an interior; at least one opticalcomponent within the interior of the housing; a front face with a cableexit; and, a first optical fiber cable within the interior extendingfrom the connector of the rear face to the optical component, and atleast one second optical fiber cable extending from the opticalcomponent to the cable exit of the front face.
 3. The telecommunicationsassembly of claim 1, wherein the rear face of the module is positionedforward of a rear most extension of the housing of the module.
 4. Thetelecommunications assembly of claim 1, wherein the holder positions theat least one adapter forward of the back of the chassis.
 5. Thetelecommunications assembly of claim 2, wherein the first optical fibercable within the module is a multi-fiber cable including a plurality ofoptical fiber strands, the optical component is a fanout, and aplurality of second optical fiber cables extend from the opticalcomponent to the cable exit of the front face, each second optical fibercable including one of the strands of the first optical fiber cable. 6.The telecommunications assembly of claim 2, wherein the opticalcomponent is an optical splitter, the first optical fiber cable includesa single strand of fiber and a plurality of second optical fiber cablesextend from the optical component to the cable exit of the front face.7. The telecommunications assembly of claim 1, wherein each moduleincludes a pair of opposing mounting flanges and each mounting locationincludes a pair of opposing slots to receive the flanges of the modules,one of the flanges larger than the other and only one of the slots sizedto receive the larger flange.
 8. The telecommunications assembly ofclaim 1, wherein the holder is positioned adjacent one of the sides ofthe chassis and includes a forward extension along the adjacent side tothe front opening, the forward extension releasably held to the chassisby a removable fastener.
 9. The telecommunications assembly of claim 8,wherein the removable fastener is a thumbscrew captively held by theforward extension of the holder and removably received within a fasteneropening of the chassis.
 10. The telecommunications assembly of claim 2,wherein the module includes a pair of fiber optic connectors on the rearface, the holder includes two fiber optic adapters which each receiveone of the fiber optic connectors, and the module includes a pair ofoptical components.
 11. The telecommunications assembly of claim 2,wherein the module includes a pair of cable exits on the front face. 12.The telecommunications assembly of claim 2, wherein each of the at leastone cable exits includes a bell shaped portion to provide bend radiusprotection to the second optical fiber cables extending through thecable exit.
 13. The telecommunications assembly of claim 1, wherein oneof the mounting locations of the chassis further includes a fiber opticcable extending to and received within the rear of the at least one ofthe fiber optic adapters, and removal of the holder through the frontopening of the chassis allows access to the fiber optic cable receivedwithin the rear of the adapter.
 14. The telecommunications assembly ofclaim 13, wherein the fiber optic cable extending to the rear of thefiber optic adapter may be accessed by removing the holder through thefront opening of the chassis, the fiber optic cable may be removed fromthe rear of the adapter and cleaned, the fiber optic cable may bereplaced within the adapter and the holder repositioned within thechassis.
 15. A method of mounting a module within a chassis comprising:providing the chassis including a front opening and a module mountinglocation, a holder positioned within an interior of the chassis at themodule mounting location and accessible through the front opening, theholder holding a fiber optic adapter with a connector of a fiber opticcable received in a rear of the adapter, and further providing a moduleadapted to be mounted at the mounting location, the module including arear face with a fiber optic connector; removing the holder and thefiber optic adapter from the interior of the chassis through the frontopening; removing the connector of the fiber optic cable from the rearof the adapter and inspecting an endface of an optical fiber within thefiber optic cable; replacing the connector with the fiber optic cablewithin the rear of the adapter; replacing the holder within the chassisat the mounting location; inserting the module within the chassisthrough the front opening at the mounting location and engaging a frontof the adapter with the connector of the rear face of the module. 16.The method of claim 15, further providing the mounting location with apair of opposing slots and the module with a pair flanges, one of theflanges larger than the other and only one of the slots sized to receivethe larger flange, the method further comprising aligning the largerflange of the module with the slot of the mounting location sized toreceive the larger flange prior to inserting the module through thefront opening of the chassis.
 17. A telecommunications modulecomprising: a housing defining an interior and including first andsecond opposing sides, a front face, a rear face and a back defining arear-most extension of the housing; the rear face positioned adjacentone of the sides of the housing in a recess and accessible from a rearof the housing; a mounting flange extending beyond each of the side ofthe housing, one flange extending substantially further from theadjacent side than the other flange; at least one fiber optic connectormounted to the rear face and positioned to inserted into a matingadapter with a rearward movement of the housing; at least one cable exitpositioned in the front face of the housing, each cable exit including abell shaped outer extension beyond the front face; a first fiber opticcable within the interior of the housing extending from the at least onefiber optic connector of the rear face to an optical component mountedwithin the interior of the housing; a second fiber optic cable withinthe housing extending from the optical component to the at least onecable exit in the front face.
 18. A fiber optic telecommunicationschassis comprising: a housing with a first major side, a second majorside, and a pair of opposing transverse sides extending between themajor sides defining an interior with an front opening and a backsubstantially closing off the interior opposite the front opening; aplurality of mounting locations defined for telecommunications modulesinserted through the front opening with the module generally orientedparallel to one of the transverse sides; each mounting locationincluding an adapter holder positioned adjacent one of the first orsecond major sides, the adapter holder removably mounted within theinterior of the housing and including at least one fiber optic adapter,each fiber optic adapter including a front end and a rear end, each endconfigured to receive a mating fiber optic connector; each adapterholder orienting the at least one fiber optic adapter with a front endpositioned to receive the mating fiber optic connector inserted throughthe front opening toward the back and generally parallel to the sides;the adapter holder positioned to hold the at least one adapter withinthe interior of the housing at a location behind the front opening andforward of the back, so that a fiber optic cable with a mating fiberconnector may be directed to and inserted within the rear end of theadapter; the adapter holder removable from the interior of the housingthrough the front opening so that the rear end of the at least oneadapter may be accessed outside of the interior.